GB/T 4852-2002Test method for tack of pressure sensitive adhesive tapes by rolling ball (English PDF)

0237.1991 are as follows.

There are only 29 kinds of steel balls for testing in this standard, which is lack

of two steel balls which have nominal diameters of 21.431 mm and 24.606 mm

as compared with the steel balls as specified in the part 12 of JIS Z 0237.1991.

This is because there are no such two sizes of steel balls in the steel ball series

for rolling bearings in China.

The main technical differences between this standard and the pre-revised

standards are.

(1) ADD the method B. Chute rolling ball method. Therefore, the name of this

standard is changed from the "Test method for tack of pressure sensitive

adhesive tapes by bevel rolling ball" to the "Test method for tack of

pressure sensitive adhesive tapes by rolling ball".

(2) The angle of the inclined plate in the method A is generally specified as

30°, and in special cases, 20° or 40°. However, the standard before

revision does not clearly specify the angle of inclination plate in special

cases.

(3) The number of rolling balls in the method A is 33 before the revision and

5.1 Unless otherwise specified, the laboratory temperature is 23 °C ± 2 °C and

the relative temperature is 50% ± 10%.

6.1 Test piece for method A

The size of test piece. Width (10 ~ 80) mm, length more than 250 mm.

6.2 Test piece for method B

The size of test piece. Width 25 mm, length more than 100 mm.

7.1 Test device

7.1.1 The bevel ball rolling device consists of inclined plates that can be inclined

at 20°, 30°, 40° and their coupling structures, as shown in Figure 1.The parts

are as follows.

7.1.1.1 Inclined plate

The inclined plate is made of a smooth hard flat plate (glass plate, metal plate,

wood board, plastic plate, etc.).

7.1.1.2 Rolling-aid section

The rolling-aid section is made of a transparent polyester film which has a

length of more than 100 mm a thickness of about 25 µm, which is attached to

the test piece at a predetermined position. The length of rolling-aid section is

7.1.2 Rolling ball. It shall use the rolling ball of the following specifications.

7.1.2.1 Material. It is made of GCr15 bearing steel. The accuracy of the steel

ball's shape tolerance and surface roughness shall be above the grade-40 as

specified in GB/T 308.

7.2 Test methods

7.2.1 Use a level to fix the rolling ball device horizontally on the test bench. The

inclined surface is taken at a standard angle of 30°, or otherwise 20° or 40° if

necessary.

7.2.3 In order to keep the length of the rolling-aid section constant at 100 mm,

according to the size of the ball, as shown in Figure 1, adjust the center of the

ball to the starting position of the ball.

7.2.4 Us tweezers to remove the ball which is stored in the rust inhibitor. Use

the cleaning method of test rolling ball as described in 7.2.5 to clean it. After

washing it clean, place it at the starting position. Allow the ball to roll down the

rolling-aid section.

7.2.5 Cleaning of test rolling ball. Use absorbent gauze 1) to dip solvent 2) to

wipe it. After the surface is dry, use a new cleaning gauze to dip solvent to scrub

it repeatedly for more than 3 times, until it is considered clean in visual

inspection.

7.2.7 Formal test

Take 3 specimens. Use the steel ball of the largest number to carry out one

rolling ball test, respectively. If a specimen cannot adhere to the steel ball, it

may be replaced with a ball which has the number smaller than it to carry out

one test.

7.3 Test results

The test results are expressed as the median (ball number) of the steel ball

number of the rolling ball test results of 3 specimens during formal test.

8.1 Test device

8.1.1 The structure of the chute rolling ball device is as shown in Figure 2.The

tilt angle is 21°30'.

8.1.2 Rolling ball

8.2 Test methods

8.2.1 Before the test, according to the method described in 7.2.5, clean the

chute and steel ball in the test device. Do not touch them from then on.

8.2.2 Use adhesive tape and so on to fix the test piece on a hard horizontal flat

test plate (glass plate, metal plate, wood board, plastic plate, etc.). When fixing

the test piece, do not allow the test piece to bulge, wrinkle, or warp. When the

edge of test piece is warped or bulged, use another adhesive tape to fix this

part on the test plate.

8.3 Test results

The test results are expressed as the arithmetic mean of the rolling distance

the ball in the 3 test pieces.